using System;

class CalculatesNfactvurhuKfact
{
    static void Main()
    {
    //Write a program that calculates N!/K! for given N and K (1<N<K).
    //N!/K! = 5 i 6 => 0
		Console.Write("N=");
		decimal n = decimal.Parse(Console.ReadLine());
		Console.Write("K=");
		decimal k = decimal.Parse(Console.ReadLine());
		decimal factN = 1;
		decimal factK = 1;
		Console.Write("\n");
		if (n > 1 && n < k)
		{
			factK = 1;
			factN = 1;
			for (int toN = 1; toN <= n; toN++)
			{
				factN *= toN;
			}
			for (int toK = 1; toK <= k; toK++)
			{
				factK *= toK;
			}
			Console.WriteLine("Factorial by N ={0}", factN);
			Console.WriteLine("Factorial by K ={0}", factK);
			Console.WriteLine();
			double result = -3;
			result = (double)factN / (double)factK;
			Console.Write("N!/K!");
			Console.WriteLine("=" + result);
		}
    }
}